Comparing membrane resistance and absorption performance of three different membranes in a gas absorption membrane contactor

Hollow fiber membrane contactors have been studied extensively in the last decade. Gas absorption membrane (GAM) contactors are a developing technology that overcome the disadvantage of conventional equipment. Three different membranes, including polytetrafluoroethylene (PTFE), polypropylene (PP), and polyvinylidene fluoride (PVDF), were used to test the performance of a GAM system in both physical and chemical absorption studies. In the physical absorption experiments, pure CO2 and de-ionized water were used in the GAM system. A Wilson plot was used to determine the membrane resistance in this work. From the results, the PVDF membrane had a higher CO2 flux than PP membranes and the highest membrane resistance. In the chemical absorption experiments, a simulated flue gas stream (15% CO2 and 85% air) was treated with monoethanolamine (MEA) solutions. Experimental results showed that the CO2 absorption performance can be ranked as PTFE > PVDF > PP. While the PTFE membrane had the best performance in the GAM system, the PVDF membrane is an alternative membrane that could be used. The stability of PTFE and PVDF membranes was tested continuously over 60 h of operation. The PTFE membranes maintained their absorption performance, while the PVDF membranes did not maintain their absorption performance over the operating time.